WASHINGTON — When Michaelyn Mankel approached Joseph R. Biden Jr. at an Iowa steak fry last month to demand dramatic action on climate change, the former vice president clasped the 24-year-old’s hands and assured her, “You’ve got a better deal from me than anybody.”
He did, after all, introduce the very first climate change legislation in Congress, in 1986, before Ms. Mankel was born. He also helped to orchestrate the “green jobs” strategy under the Obama administration’s economic stimulus package. He supported landmark regulations on coal plants and automobile tailpipe emissions as vice president, and helped to secure the Paris Agreement, the 2015 pact to limit the rise of global temperatures. His climate change plan would spend $1.7 trillion over a decade, impose a tax on greenhouse gases and aim to bring carbon emissions to net zero by 2050.
Yet Ms. Mankel, a full-time volunteer for the youth-led Sunrise Movement, was disappointed. “This far along in his campaign, it seems he is still ill-prepared to answer a serious question about the climate crisis,” she said in an interview.
And so it has gone for Mr. Biden, whose experience in the wars over climate change is unmatched among Democratic contenders for the White House, but whose image remains soporific to the young activists driving the debate.
“Times have changed,” said Nigel Purvis, a State Department climate negotiator under Presidents Bill Clinton and George W. Bush, who called Mr. Biden “a consistent and reliable climate champion” in the Senate and for the White House. But, he added, “Like most longtime Democratic politicians, Biden has a twenty-year track record of advocating for incremental measures, and today the Democratic primary base wants dramatic action.”
A new poll made public Tuesday indicated that Mr. Biden remained the front-runner among Democrats and those who count themselves as “climate voters.” But other candidates, like Elizabeth Warren, are fast closing in. Meantime, the former vice president keeps being accosted on live television and at campaign events by young activists challenging his commitment and his perceived coziness with fossil fuel interests.
It is true that Mr. Biden’s climate plan is neither the priciest nor the most ambitious — others call for reaching carbon neutrality well before midcentury. His refusal to endorse calls for a ban on hydraulic fracturing, a natural-gas extraction method commonly called fracking, may be politically pragmatic as he courts voters in Pennsylvania and Ohio, but it is not popular with activists.
Beyond the policy specifics is the sense that Mr. Biden, 76, is simply not the man of the moment. To young climate activists, his campaign has, so far, failed to capture the urgency outlined by a high-profile United Nations report that warned the Earth was on track to experience fatal heat waves and food shortages by 2040, sooner than earlier projections.
On a personal level, the candidate can’t quite connect with an incensed climate movement personified by Greta Thunberg, a 16-year-old Swedish activist who angrily chastised world leaders gathered at the United Nations last month, saying, “If you choose to fail us, I say we will never forgive you.”
Mr. Biden’s supporters seem incredulous that his record and proposals have not won young voters over.
“This is a guy who was introducing bills on climate change before this was on the radar screen of most politicians,” said Jake Sullivan, who served as Mr. Biden’s national security adviser in the White House. “He’s somebody who talks about the issue in an incredibly passionate and purposeful way.”
Mr. Biden’s campaign challenged the belief among many younger activists that the former vice president is not likely to make climate change a top priority if elected.
“There are some folks in the climate movement who are very vocal,” said Stef Feldman, Mr. Biden’s policy director. “There are also folks who are believers in the drastic efforts that we need to do to combat climate change who think Joe Biden is the best one equipped to address the challenge, because he has the experience of bringing other countries to the table.”
But other issues keep drowning out that message. Questions about Mr. Biden’s ability to energize voters on climate change come as national political attention is focused on accusations that President Trump put pressure on the Ukrainian government to investigate Mr. Biden and his son, Hunter Biden, who once sat on the board of a Ukrainian company, Burisma.
Trump supporters might focus on Hunter Biden’s monthly salary, as much as $50,000. Climate activists are more concerned about Burisma’s business: natural gas.
Fossil fuels and Mr. Biden’s support for them are at the heart of the climate movement’s concerns. Three other Democratic contenders — Senator Kamala Harris of California, Senator Elizabeth Warren of Massachusetts and Senator Bernie Sanders of Vermont — have called for a national ban on fracking. Mr. Biden has not.
(Experts have noted that an outright ban on fracking across the United States would require an act of Congress and could not be done by executive action. However, there are regulatory steps a president could take to limit the practice.)
Heather Zichal, an informal adviser to Mr. Biden’s campaign who helped write domestic climate change policies in the Obama administration, served until recently on the board of Cheniere Energy, a liquefied natural gas export company. In September, Mr. Biden attended a fund-raiser hosted by Andrew Goldman, co-founder of another natural gas company, Western LNG.
Isaac Larkin, a 27-year-old biologist, asked Mr. Biden about that fund-raiser during a forum on climate change on CNN last month and accused the candidate of violating a pledge not to accept money from fossil fuel executives. Mr. Biden responded that Mr. Goldman did not meet that definition because he was no longer involved with the day-to-day operations of the company and did not sit on the board.
Mr. Larkin, in an interview, criticized “Biden’s attempt to clip hairs about who is or isn’t technically a fossil fuel executive.” He also took issue with the position of the Obama administration that natural gas is an important “bridge fuel” to transition from coal to renewable sources like wind and solar.
“The bridge is on fire and we need to get off the bridge and get to a new place immediately,” Mr. Larkin said.
Ms. Feldman noted that the former vice president has called for banning oil and gas drilling on public lands. She also said that even the Intergovernmental Panel on Climate Change, a group of scientists convened by the United Nations to guide world leaders in policymaking, has acknowledged a role for natural gas as a way to reduce emissions from coal plants.
Of course, no Democratic plan has a chance without the White House, and no Democrat will win the presidency without swing states where the fossil fuel industry employs thousands, such as Pennsylvania, which Mr. Trump won by less than 1 percentage point. Mr. Biden was born in Scranton, Pa.
Christopher Borick, director of the Muhlenberg College Institute of Public Opinion, said it was possible for a candidate who opposes fracking to win Pennsylvania, but he said that was not Mr. Biden’s style.
“His approach is staying close to the middle, giving enough strength on environmental issues to show he’s a vast improvement over the president and hope that does the trick,” Mr. Borick said. “That’s consummate Biden.”
That style rubs young voters like Ms. Mankel the wrong way. She acknowledged that she was unfamiliar with most of the Obama administration’s signature regulations to rein in greenhouse gases. She said she was sure they were ambitious compared to what came before.
“But frankly,” she added, “they weren’t enough.”
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